A new study has found a decline in drinking rates, especially among younger adults, for the first time since a widespread surge in U.S. alcohol use during the pandemic.

But researchers also say that along with the positive news there is data that points to a different trend: sustained increases in heavy drinking among some older people.

According to a study published at the end of September that analyzed data from the Centers for Disease Control and Prevention’s annual National Health Interview Survey, rates of both overall and heavy drinking have maintained an upward trajectory in adults 50 to 64.

Medical experts note there are special concerns for this age group because the behavior carries both an elevated risk of serious illnesses, such as cirrhosis, cancer, and heart disorders, and a potential rise in acute issues associated with advancing age, like tripping and falling.

“Heavy drinking basically worsens every problem you can think of that that comes with older age,” said Kenneth Mukamal, professor of medicine at Beth Israel Deaconess Medical Center whose research has examined the role of alcohol consumption in older adults’ health.

The number of the older adults who reported regular drinking over the past year has increased roughly 5 percent over the last decade, while the share of heavy drinkers rose from just over 5 percent to roughly 7.5 percent over the same time, according to the study.

For men, heavy drinking was defined as five or more drinks per day or an average of 15 or more per week, and for women, four or more per day or an average of eight or more per week in the 12 months before the survey.

According to CDC data, Americans of retirement age historically drank the least, followed by their slightly younger counterparts in the 50- to 64-year-old range.

But, the data shows, that began to shift roughly 10 years ago when Gen X drinkers (born between 1965-1980) surpassed rates of teen and young adults who reported drinking — a gap that has continued to widen in recent years. Gen Xers now range from 46 to 61 years old.

And retirees are catching up too. For those over the age of 65, regular drinking has increased at roughly the same rate as their Gen X counterparts, while heavy drinking has risen just over 1 percent.

According to Jagpreet Chhatwal, director of the Center for Health Technology Assessment at Mass General Brigham, these figures could foreshadow a rise in adverse health outcomes.

“If somebody’s drinking at that age, it’s not that they just started drinking now,” Chhatwal said. “The liver keeps absorbing that shock for a long time, without many people really knowing, and that’s when with prolonged exposure to alcohol, especially heavy drinking, can cause huge damage to the liver, resulting in cirrhosis, liver cancer, and end-stage liver disease.”

Perhaps one of the best-understood acute effects of drinking, Mukamal added, is changes to heart rhythm.

“Alcohol precipitates heart rhythm disturbances like atrial fibrillation, and a-fib is vastly more common amongst older adults,” Mukamal said. “Even a single drink probably doubles somebody’s risk.”

And there are other safety concerns.

“The speed of metabolism of alcohol declines with age, so that the same amount of alcohol translates to a greater effective dose in an older adult. Older adults also tend to lose weight and muscle mass and the tissues that alcohol distributes into, which means that the same amount of alcohol is effectively at a higher level in what’s left,” he said. “Because elimination is slowed, a similar amount of alcohol potentially represents a bigger dose for an older adult.”

Alcohol increases the risk of reduced balance and perception, and worsens the lessened ability to right oneself that comes with age, Mukamal said.

“And the consequences of falling for older adults are very substantial, with things like hip fractures,” he said.

Moreover, older adults are likelier to take prescription medications that have side effects that can be intensified by alcohol, including sedation, he added.

 But Chhatwal noted that while the trends may be concerning, change is possible.

“We don’t know yet if a drop in drinking in younger generations is a fluctuation or a consistent trend, while on the other hand it’s harder to break long-term drinking patterns among older generations, who have been drinking consistently for decades,” he said. But, “if people stop drinking, the liver starts improving. Once it’s end-phase liver disease, then it’s too late.”